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author | Marcel Ziswiler <marcel.ziswiler@toradex.com> | 2015-12-15 14:51:17 +0100 |
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committer | Marcel Ziswiler <marcel.ziswiler@toradex.com> | 2015-12-15 14:51:17 +0100 |
commit | e6d111cd909551cec5902358db1e25dcaa8c86bb (patch) | |
tree | 99673aec563c76a1a4d7ca2d31b90b47549ae40b /Documentation/devicetree/bindings/mfd/mfd.txt | |
parent | 1dcb97e485420a25461cc44d43f987c8bbf50e7a (diff) | |
parent | 07cc49f66973f49a391c91bf4b158fa0f2562ca8 (diff) |
Merge tag 'v4.1.15' into toradex_vf_4.1-nextColibri_VF_LinuxImageV2.5Beta3_20151215
This is the 4.1.15 stable release
Diffstat (limited to 'Documentation/devicetree/bindings/mfd/mfd.txt')
-rw-r--r-- | Documentation/devicetree/bindings/mfd/mfd.txt | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/mfd/mfd.txt b/Documentation/devicetree/bindings/mfd/mfd.txt new file mode 100644 index 000000000000..af9d6931a1a2 --- /dev/null +++ b/Documentation/devicetree/bindings/mfd/mfd.txt @@ -0,0 +1,41 @@ +Multi-Function Devices (MFD) + +These devices comprise a nexus for heterogeneous hardware blocks containing +more than one non-unique yet varying hardware functionality. + +A typical MFD can be: + +- A mixed signal ASIC on an external bus, sometimes a PMIC (Power Management + Integrated Circuit) that is manufactured in a lower technology node (rough + silicon) that handles analog drivers for things like audio amplifiers, LED + drivers, level shifters, PHY (physical interfaces to things like USB or + ethernet), regulators etc. + +- A range of memory registers containing "miscellaneous system registers" also + known as a system controller "syscon" or any other memory range containing a + mix of unrelated hardware devices. + +Optional properties: + +- compatible : "simple-mfd" - this signifies that the operating system should + consider all subnodes of the MFD device as separate devices akin to how + "simple-bus" inidicates when to see subnodes as children for a simple + memory-mapped bus. For more complex devices, when the nexus driver has to + probe registers to figure out what child devices exist etc, this should not + be used. In the latter case the child devices will be determined by the + operating system. + +Example: + +foo@1000 { + compatible = "syscon", "simple-mfd"; + reg = <0x01000 0x1000>; + + led@08.0 { + compatible = "register-bit-led"; + offset = <0x08>; + mask = <0x01>; + label = "myled"; + default-state = "on"; + }; +}; |